Large Robot Sound System

I have a very large robot (4 feet tall 2 feet wide) and I am looking to put a sort of sound system in it to play music. The robot is powered off of a 36 amp and hour sealed lead acid battery.

-I would like to have at least 1 speaker or more -I do not want the sound system drawing more than a continuous 10 amps at maximum volume -I would like to do this for under 100$

How can I go about doing this?

Someone recommenced a car audio system. Would this be wise?

Boom-Bot ?